5-20
Chadwick-Helmuth A Business Unit of Honeywell International, Inc.
Chapter 5
- Maintenance And Repair
ad.
Repeat steps r through ac for the Velocimeter channel and magnetic pickup channel
combinations listed in Table 5-4.
5.5.2.4
Channel Crosstalk Test
This test measures the amount of energy induced by a signal on another 8520C channel. This is done
by placing a signal level on one channel and then measuring the relative signal amplitude of the other
channels listed in Table 5-5.
a.
Connect cable 8278 to Velocimeter channel 1 and remove cable 10502 from magnetic
pickup channel. Set up signal generator as follows:
(1)
For channel connected to magnetic pickup input, set to Frequency = 100.00 +/-
0.1 Hz, Waveform = Sine wave, Amplitude = 19.0 mV pk.
(2)
Monitor signal generator output with spectrum analyzer with marker at 100 Hz.
Adjust signal generator output channel connected to Velocimeter input until
amplitude is 13.44 +/- 0.05 mV RMS.
b.
Press
SPECTRUM
key on 8500C/C+.
c.
Press
SETUP
key.
d.
Key in
1000 <Hz>
with numeric keys.
e.
Select
SEEK
field with arrow keys.
f.
Press
CHANGE
soft key to select
<SEEK OFF>
.
g.
Select
INPUT
field with arrow keys.
Table 5-5. Suggested 8520C Velocimeter Channel Crosstalk Combinations
Velocimeter
Channel
(Cable 8278)
Velocimeter
Channels
(selected one at a time in test
step)
1
2-12
2
3-12
3
4-12
4
5-12
5
6-12
6
7-12
7
8-12
8
9-12
9
10-12
10
11-12
11
12
